Interview questions

Lowest Common Ancestor of a Binary Tree II

Given a binary tree and two target nodes p and q, return their lowest common ancestor if and only if both targets exist in the…

Companies: Amazon, Meta

Last reported Nov 2025

Maximum Profit From Trading Stocks

Given an array of daily stock prices and trading constraints (e.g., limits on number of transactions, transaction fees, or cooldowns), compute the maximum profit achievable…

Companies: Meta

Last reported Nov 2025

Find the Kth Smallest Element Across Multiple Sorted Lists

Given M sorted lists of potentially different lengths, find the Kth smallest (or largest) element across all lists. Each individual list is sorted in ascending…

Companies: Meta

Last reported Nov 2025

String Matching in an Array (Substring Containment)

Given an array of strings, identify which words appear as substrings of any other word in the array (equivalently, find which words do NOT appear…

Companies: Meta

Last reported Nov 2025

for the technical phone screen both questions were leetcode tagged. You can not run your code on coderpad. You have to dry run your solution.

Companies: LinkedIn

Last reported Nov 2025

It was hard with parsing through stocks or something, had to use a 2d array.

Companies: Palantir

Last reported Nov 2025

leetcode medium questions how much letters do we want to chane to get palindrom word

Companies: NVIDIA

Last reported Nov 2025

Target Sum

Count how many ways to assign +/− to each element of nums so the signed sum equals target. This reduces to a subset-sum problem: count…

Companies: Meta, Pinterest

0-1 Knapsack · Array · Backtracking · Dynamic Programming

Last reported Nov 2025

The technical question was a Data Structures and Algorithms question of Leetcode Medium but couched in a way that initially made it seem like a finance question initially, as it was about balances. There was an expectation that you would be able to implement the required algorithm from memory.

The technical question was a Data Structures and Algorithms question of Leetcode Medium but couched in a way that initially made it seem like a…

Companies: Citadel

Last reported Nov 2025

Typical leetcode stuff; complexity, testing, style, etc.

Companies: Databricks

Last reported Nov 2025

Implement delimiter-free string codec

Companies: OpenAI

Parsing & Interpreters

Last reported Oct 2025

Read CSV Data and Print Randomized Output

Write code that reads data from a CSV file and prints the data in a randomized order.

Companies: Clio

Last reported Oct 2025

Simulate turn-based monster team battle

Companies: OpenAI

Low-Level Design (OOP) · Simulation & State Machines

Last reported Oct 2025

Add Two Numbers

Companies: Amazon, Bloomberg, Google, Meta +2

Linked List · Math · Recursion

Last reported Oct 2025

Binary Tree Upside Down

Transform a binary tree by flipping it upside down so the original leftmost node becomes the new root and each parent becomes the right child…

Companies: LinkedIn

Last reported Oct 2025

Find Second Largest and Second Smallest Elements in Array

Given an array of integers, write a function to find and return both the second largest and second smallest elements. Handle edge cases where the…

Companies: Amazon

Last reported Oct 2025

Sliding Puzzle

Given a 2x3 sliding puzzle with tiles 1–5 and a blank (0), find the minimum number of swaps of 0 with its 4-directional neighbors to…

Companies: Amazon, Microsoft

Last reported Oct 2025

Design a single- and multi-threaded web crawler

Companies: Anthropic

Concurrency · Graphs

Last reported Oct 2025

Minimum Time to Type Word Using Special Typewriter

Compute the minimum seconds to type a given word on a circular typewriter (letters 'a'–'z') with the pointer starting at 'a', where moving one step…

Companies: JPMorgan Chase

Last reported Oct 2025

Implement a Task Queue

Design and implement a task queue system that can accept, store, and process tasks in a first-in-first-out manner. The implementation should support basic operations like…

Companies: Uber

Last reported Oct 2025

Remove Nth Node From End of List

Companies: Meta

Last reported Oct 2025

Compute time to infect all cells

Companies: OpenAI

Graphs · Grids & Matrices

Last reported Oct 2025